DE112016006027B4 - SINGLE AXIS PROGRESSIVE SCREW PUMP - Google Patents

Abstract

A uniaxial progressive cavity pump comprising a housing (29), the housing (29) containing: a stator (32) having an internally threaded peripheral surface; a rotor (33) configured to be insertable into the stator (32). and which is formed of an externally threaded stem body;an outer body (31) disposed on an outside of the stator (32) and configured to be between a first position in which the outer body (31) is configured thereto movable to compress the stator (32), and a second position in which the outer body (31) reduces at least one state of compression of the stator (32), the outer body (31) having a pair of end portions each having a pair of side surfaces a pair of adapters (55, 56) provided at respective end portions of the outer body (31) and each including a recessed portion (58), each of the recessed portions having opposite surfaces for foot ears of both side surfaces of an associated one of the respective end portions of the outer body (31), and each of the recessed portions (58) is opened to an outer diameter side of the associated adapter (55, 56); anda sleeve (30) disposed on an outer diameter side of the outer body (31) and forming a hermetically sealed space (52) between the sleeve (30) and the housing (29), the sleeve (30) being constructed to be elastic being deformable in an inner diameter side of the sleeve (30) by filling a control fluid into the hermetically sealed space (52).

Description

TECHNICAL AREA

The present invention relates to a uniaxial progressive cavity pump.

STATE OF THE ART

In general, in a uniaxial progressive cavity pump, a stator expands and contracts in response to a change in a liquid temperature or an atmosphere temperature. Therefore, there may be a case where it is difficult to convey a fluid material in an appropriate state matching such a change. For example, in CIP (cleaning in place), or SIP (sterilizing in place), high-temperature steam or hot water is caused to flow into the pump, and hence the problem explained above arises. That is, in CIP or SIP, high-temperature steam or water is caused to flow into the pump to clean or sterilize the inside of the pump after pumping a fluid material (food, chemicals, or the like) at room temperature . In this operating state, the stator is enlarged such that interference becomes excessively large, whereby a frictional force between the rotor and the stator becomes large when interference between a rotor and a stator is set to a value close to a fluid material at room temperature. As a result, a torque required to rotate the rotor increases, or the stator wears out or is damaged before the end of an expected life. On the other hand, if pre-care is taken to keep mutual interference between the rotor and stator small by considering the expansion of the stator, which may be caused by high-temperature steam or hot water that must flow during CIP or SIP a fluid material cannot be adequately pumped at room temperature.

Conventionally, as a uniaxial progressive cavity pump capable of solving such a problem, there has been known a uniaxial progressive cavity pump having the following structure. In a state where a stator made of an elastic material is housed inside a case and a rotor is inserted into the stator, an air pressure in a space formed between the case and the stator is adjusted so as to elastically deform the stator Deformed towards the inside, thereby maintaining a contact pressure between the stator and the rotor at a fixed value (see, for example, the JP S60-173 381 A ).

However, it is difficult to appropriately control a pressure in the space for maintaining a contact pressure between the stator and the rotor to a fixed value. For example, when the pressure is large, a cavity, which is a space for pumping a fluid material, formed between the rotor and the stator becomes so small that the pump cannot receive a desired discharge amount. In addition, a frictional force between the rotor and the stator becomes large, so that a torque required for rotating the rotor increases, or the stator wears out before the end of an expected life. On the other hand, when the pressure is small, even if the rotor rotates, a sufficiently smooth flow of a fluid material cannot be secured, making it impossible to discharge the fluid material at a desired discharge pressure.

In addition, air pressure acts directly on the stator, and consequently air may leak through a damaged portion when damage such as a crack occurs in the stator. In this case, it is difficult to press the stator onto the rotor with a desired holding pressure. There may also be a case where air is mixed into a fluid material through the damaged portion or a fluid material leaks from the damaged portion. Mixing of air into a fluid material (especially food) can cause a quality problem. On the other hand, when a fluid material leaks into the environment, a portion of the environment is polluted by the leakage.

The DE 41 16 697 C1 12 shows a stator casing 12 pressing on a stator lining 22 and a guide part (housing parts 32, 34 of a connecting piece 36) which guides movement in the circumferential direction and allows the outer body 12 to burst open in the radial direction at a separating region 14. In contrast, the stator casing 12 is not designed for an adjustment in the radial direction. Therefore, the mutual influence of the stator and rotor, more precisely the influence of the stator on the rotor, cannot be changed.

The DE 2 331 173 A1 , the EP 1 326 023 A2 , the JP2010-1 876A and the U.S. 3,028,812 A each show progressing cavity pumps, but no structure in which the stator can be pressurized via a sleeve and a control fluid.

BRIEF EXPLANATION OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

It is an object of the present invention to provide a uniaxial progressive cavity pump which can stably adjust a contact pressure between a stator and a rotor so that a fluid material can be discharged at a desired discharge pressure and damage to the stator occurs minimally.

FACILITIES TO SOLVE THE PROBLEMS

• einen Stator, der eine Innenumfangsfläche mit Innengewinde aufweist;
• einen Rotor, der dazu aufgebaut ist in den Stator einführbar zu sein, und aus einem Schaftkörper mit Außengewinde gebildet ist;
• einen Außenkörper, der dazu aufgebaut ist, zwischen einer ersten Position, an der der Außenkörper dazu fähig ist, den Stator zusammenzudrücken, und einer zweiten Position, an der der Außenkörper zumindest einen Kompressionszustand des Stators abschwächt, bewegbar zu sein; und
• ein Führungsteil, das dazu aufgebaut ist, eine Bewegung des Außenkörpers in einer Umfangsrichtung des Stators einzuschränken, während es eine Bewegung des Außenkörpers in einer Radialrichtung des Stators erlaubt, indem es einen Endabschnitt des Außenkörpers führt.

As a means for solving the above problem, the present invention provides a uniaxial progressive cavity pump, comprising:

• a stator having an internal peripheral surface with internal threads;
• a rotor configured to be insertable into the stator and formed of a male-threaded shaft body;
• an outer body configured to be moveable between a first position at which the outer body is capable of compressing the stator and a second position at which the outer body relieves at least one state of compression of the stator; and
• a guide part configured to restrict movement of the outer body in a circumferential direction of the stator while allowing movement of the outer body in a radial direction of the stator by guiding an end portion of the outer body.

With such a configuration, an interference can be adjusted to an appropriate value such that a fastening force of the stator to the rotor becomes stable only by moving the position of the outer body between the first position and the second position. That is, it is possible to set an appropriate fixing range that matches a degree of expansion of the stator due to a temperature difference of a fluid material or an atmosphere temperature, and thus it is possible to prevent deterioration of the stator, increase in torque of the rotor, or change of a discharge pressure of a fluid material.

In addition, the outer body is prevented from moving in the circumferential direction of the stator by the guide part, and therefore the outer body is not allowed to rotate along with the rotation of the rotor. Accordingly, although the rotation of the stator has conventionally been prevented only at an end portion of the stator, the rotation of the stator can also be prevented by the guide member, and hence the stator is minimally damaged by repeated fatigue.

The end portion of the outer body may have an engaging portion on an end surface thereof, and
the guide member may have a portion to be engaged that positions the engagement portion in the circumferential direction while allowing movement of the engagement portion in the radial direction of the stator.

The uniaxial progressive cavity pump may further include a mounting portion to which the guide member is mounted, and
the guide part may be formed in a ring shape and may be mounted on the mounting portion.

The guide member is preferably formed of plural guide portions formed by dividing the guide member in the circumferential direction, and
the plural guide portions are preferably mounted on the mounting portion in an annular continuous state.

With such a configuration, the guide member formed of the multiple guide portions can be easily assembled in an annular continuous state using the assembling portion. In addition, the assembling operation can be easily performed compared to the case where the guide member is formed of a single piece.

Preferably, the guide member and the mounting portion form a sliding structure configured to move the respective guide portions to an inner diameter side such that inner surfaces of the respective guide portions are in close contact with an outer surface of the stator when the mounting portion is connected to the guide member.

With such a structure, the respective guide portions can be moved to the inner diameter side only by connecting the mounting portion to the guide member by the sliding structure, and hence the guide member can be stably supported and the sealability at the end portion of the stator can be improved.

A reinforcement body is preferably provided integrally with the outer body.

With such a structure, for example, the outer body can obtain sufficient strength even when the outer body is made of a synthetic resin. Consequently, the deformation of the outer body can be effectively prevented.

The uniaxial progressive cavity pump preferably further includes a drainage structure for draining steam or water from a space where the stator and the outer body are arranged.

With such a structure, steam can be safely discharged through the drainage structure even if steam penetrates through the stator and reaches the outside of the stator, and thus the remaining of steam or water in the space can be prevented.

EFFECT OF INVENTION

According to the present invention, movement of the outer body in the radial direction of the stator is allowed, and hence interference between the rotor and the stator is freely changeable, whereby a fastening force can be adjusted to an appropriate value. In addition, a movement of the outer body in the circumferential direction of the stator is restricted, and consequently a torque load generated along with the rotation of the rotor can be distributed, whereby a torque load acting on the end portion of the stator is relaxed, preventing the occurrence of damage at the end portion of the stator is prevented.

character list

• 1 12 is a schematic sectional view of a uniaxial progressive cavity pump according to an embodiment.
• 2 13 is a partially enlarged view showing a drive transmission portion in FIG 1 shows.
• 3A Fig. 12 is a front view of an adjustment plate (with a back view being the same as the front view), 3B is a plan view of the adjustment plate, 3C Figure 12 is a right view of the adjustment plate (where left view corresponds to right view), 3D 12 is a bottom view of the adjustment plate and 3E 12 is a perspective view of the adjustment plate.
• 4 12 is a partial sectional view showing one end side of a pump body in FIG 1 shows.
• 5 12 is a partial sectional view showing the other end side of the pump body in FIG 1 shows.
• 6A is a front view of an in 1 shown outer body, and 6B is a side view of the outer body.
• 7A is a front view of an in 1 shown adapter, and 7B 13 is a sectional view of the adapter taken along a line AA in FIG 7A .
• 8th Fig. 13 is a broken front view showing an engaged state shown in Fig 1 between projections of an outer portion and recessed portions formed in the adapter.
• 9 FIG. 12 is a sectional view showing a state at the time of starting to mount the rotating ring temporary fixing adjustment plate as in FIG 1 shown shows.
• 10 Fig. 14 is a sectional view showing a state in which the rotating ring is made of a in 9 state shown is pushed.
• 11 Fig. 14 is a sectional view showing a state in which the adjustment plate is caused to deviate from an in 10 shown state.
• 12 Fig. 12 is a sectional view showing a state in which an in 11 In the state shown, a positioning pin of the rotating ring is inserted into a pin hole formed in the adjusting plate.
• 13 Fig. 14 is a perspective view showing a state in which the adjusting plate is operated to move the adjusting plate from an in 9 shown state to a in 10 state shown.
• 14A is a cross-sectional view of FIG 1 shown pump body in which outer portions are located at their innermost diametrical positions, and 14B Fig. 12 is a cross-sectional view showing a state in which the respective outer portions are made of an in 14A shown state are moved to a side of an outer diameter.
• 15A 13 is a front sectional view of an outer body according to another embodiment, 15B 13 is a sectional view in the transverse direction of the outer body and 15C is an exploded view of the in 15B shown outer body.
• 16A 12 is a partially enlarged view showing a drive train according to another embodiment, and 16B 12 is a plan view of the power train.

MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention are described below with reference to attached figures. The following description mainly illustrates the embodiment of the present invention, and the description is not intended to limit the present invention, a product incorporating the present invention, or the use of the present invention. In addition, drawings are shown schematically, and the proportions of respective parts and the like are different from those of actual parts.

1 shows a uniaxial progressing cavity pump according to this embodiment. The uniaxial progressive cavity pump includes: a drive unit (not shown in the figure) disposed on one end side of a first casing 1; and a pump body 2 arranged on the other end side of the first housing 1 . The uniaxial eccentric screw pump is mounted on a stand or machine bed 3.

The first housing 1 is a cylindrical body made of a metal, and a coupling rod 4 is arranged inside the first housing 1 . A connection pipe 5 is connected to an outer peripheral surface of the first housing 1 on one end side, and a fluid material can be supplied to the first housing 1 from a tank (not shown in the figure) or the like. An end portion of the coupling rod 4 is connected to a power transmission portion 6 on a power unit side.

As in 2 As shown, the drive train 6 comprises a drive shaft 9 rotatably supported by bearings 8 in a second housing 7 . The drive shaft 9 is rotated by driving the drive unit. A cylindrical portion 10 is formed at a distal end of the drive shaft 9 and an end portion of the coupling rod 4 is inserted into the cylindrical portion 10 . The coupling rod 4 and the drive shaft 9 are connected to each other by fitting a connecting pin 11 into the coupling rod 4 and the drive shaft 9 . With such a structure, the power of the driving unit is transmitted to the coupling rod 4 .

A mechanical seal 12 is mounted on an outer periphery of an end portion of the coupling rod 4 . The mechanical seal 12 includes a fixed ring 14A and a rotating ring 14B.

The fixed ring 14A is formed by placing a seat ring 13 on the inside of a seal cover 14a with an O-ring 14b therebetween. An annular protruding portion 13a is formed on an end face of the seat ring 13. As shown in FIG.

The rotating ring 14B is formed of a driven ring 15 and an annular portion 16. As shown in FIG. The driven ring 15 has an inner peripheral surface with a stepped shape, and a small-diameter inner peripheral surface of the driven ring 15 is brought into contact with an outer peripheral surface of the coupling rod 4 . An O-ring 17 is mounted on a large-diameter inner peripheral surface of the driven ring 15 so that the O-ring 17 comes into contact with a stepped portion defined between the large-diameter inner peripheral surface and the small-diameter inner peripheral surface of the driven ring 15 is formed. The annular portion 16 is mounted on the clutch rod 4 such that the annular portion 16 is reciprocally movable in an axial direction relative to the driven ring 15 by a guide pin 18 . The annular portion 16 is biased in a direction away from the driven ring 15 by a spring 19 . A positioning pin 20 is integrally formed on an end face of the annular portion 16 .

A pair of groove portions 22 (mounting grooves) are formed on the outer peripheral surface of the coupling rod 4 . The groove portions 22 have flat surfaces 21 (bottom surfaces) formed orthogonal to a radial direction and an axial direction of the coupling rod 4 and parallel to each other. The adjusting plate 23 is mounted on the coupling rod 4 by using these groove portions 22 so that removal of the rotating ring 14B in the axial direction is prevented and the rotating ring 14B can be fixed to the coupling rod 4 temporarily.

The adjustment plate 23 is a plate-like body formed by performing press processing on a metal such as stainless steel. As in 3 As shown, the adjusting plate 23 is formed of: a pair of leg portions 24 and a connecting portion 25 connecting these leg portions 24 to each other.

The leg portions 24 are shaped so that a distance between inner surfaces of the leg portions 24 facing each other is equal to a size in a width direction between the flat surfaces 21 formed on the coupling rod 4 (with a clearance that allows arranging the leg portions 24 on the flat faces 21 allowed). An extended portion 26 having a sector shape is formed at lower end portions of the leg portions 24, respectively. The extended portions 26 are formed to match the position of the center of gravity of the adjusting plate 23 with an axis of the connecting rod 4 when the adjusting plate 23 is mounted on the connecting rod 4 . With such a configuration, the movement of the adjusting plate 23 toward an outer diameter side can be suppressed even when the coupling rod 4 is rotated so that a centrifugal force acts on the adjusting plate 23 . Outer peripheral edges of the extended portions 26 are positioned on the same circumference across the position of the center of gravity of the adjusting plate 23 . Accordingly, an expansion area of the adjusting plate 23 around a surrounding area can be minimized.

A pin hole 27 is formed in a central portion of the connecting portion 25 . The positioning pin 20 formed on the annular portion 16 of the rotating ring 14B is inserted into the pin hole 27 so that the position of the rotating ring 14B is restricted in the radial direction with respect to the adjusting plate 23 mounted on the coupling rod 4 . An operating projection 28 projects from both ends of an upper portion of the connecting portion 25 . As will be described later, the operating projections 28 are used at the time of mounting the adjusting plate 23 onto the coupling rod 4 or at the time of removing the adjusting plate 23 from the coupling rod 4.

In a state where the rotary ring 14B is temporarily fixed to the coupling rod 4 by the adjusting plate 23, the drive shaft 9 is connected to the coupling rod 4 on a driving unit side. When connecting the drive shaft 9 to the coupling rod 4, the adjusting plate 23 is pushed in an axial direction through an opening edge portion 9a at the distal end of the drive shaft 9 so that the adjusting plate 23 is located at an appropriate position. Accordingly, power can be transmitted from the drive unit to the clutch rod 4 . In such a state, the leg portions 24 of the adjusting plate 23 are engaged with the groove portions 22 formed on the coupling rod 4 so that a rotational force of the coupling rod 4 is transmitted to the adjusting plate 23 . The positioning pin 20 of the rotating ring 14B engages with the pin hole 27 formed in the adjusting plate 23 so that a rotational force of the adjusting plate 23 is transmitted to the rotating ring 14B. That is, the adjusting plate 23 is used in positioning the rotating ring 14B in the axial direction of the coupling rod 4, in transmitting a rotational force from the coupling rod 4 to the rotating ring 14b, and as a tool used in assembling the rotating ring 14B.

Back to 1 For example, the pump body 2 is a part in which a sleeve 30, an outer body 31, a stator 32 and a rotor 33 are housed in a third casing 29. As shown in FIG.

As in 4 An end fitting 34 is shown mounted on an end portion of the third housing 29 . The end piece 34 has a hollow-cylindrical shape. An inner peripheral surface of the end port 34 on an end side increases toward an outer diameter side, and an end portion of the stator 32 is disposed in the enlarged portion in a press-fitted state. An annular protruding portion 35 is formed on an end face of the end port 34 . As described later, the annular protruding portion 35 plays a role in shifting two adapter portions 57 constituting a first adapter 55 toward the inner diameter side, thereby bringing inner surfaces of the adapter portions 57 into pressure contact with an outer surface of the stator 32. A connecting portion between the third housing 29 and the end port 34 is sealed by packing or the like not shown in the figure.

As in 5 As shown, a locking member 36 and a protective cover 37 are mounted on the other end portion of the third housing 29. As shown in FIG. An inner peripheral surface of the locking member 36 on one end side is enlarged toward the outer diameter side, and the other end portion of the stator 32 is placed in a press-fitted state in the enlarged portion. An end surface of the locking member 36 faces the inside of the third housing 29 and an annular protruding portion 38 is formed on an outer peripheral edge of the locking member 36 . As described later, the annular protruding portion 38 pushes two adapter portions 57 of the second adapter 56 toward the inner diameter side, thereby bringing inner surfaces of the adapter portions 57 into pressure contact with the outer surface of the stator 32 . A connecting portion between the third case 29 and the closure member 36 is sealed by a packing or the like not shown in the figure. The protective cover 37 covers the other end portion of the third case 29 and a portion of the locking member 36 .

Again referring to 1 An inlet port 39 is connected to a lower middle portion of the third housing 29 and an outlet port 40 is connected to an upper middle portion of the third housing 29 . A first on/off valve 41, a control valve 42, a first pressure gauge 43 and a regulator 44 (Pressure regulator) are arranged at a middle portion of a pipe sequentially from a side of the third housing connected to the inlet port 39 . With such a construction, a pressure of a supplied control fluid (the fluid preferably being an incompressible fluid represented by a liquid, although the fluid may be a gas) is adjusted by the regulator 44 and the fluid can be controlled via the control valve 42 , whose operating position is switched to an open position, the opened first on/off valve 41 and the inlet port 39 are inserted into a hermetically sealed space, which will be described later. A second pressure gauge 45 and a second on/off valve 46 are sequentially arranged from the third housing side at a middle portion of a pipe connected to the outlet port 40 . The second pressure gauge 45 detects a pressure of the control fluid in the hermetically sealed space 52. A detected pressure is read into a control device not shown in the figures. The control device adjusts a flow rate and a pressure of the control fluid filled in the sealed space 52 via the inlet port 39 based on the read detected pressure, and opens/closes the second open/close valve 46 such that the control fluid in the hermetically sealed space 52 can be discharged.

An air inlet 47 is formed at an upper portion of one end portion of the third case 29 , and an air outlet 48 is formed at a lower portion of the other end portion of the third case 29 . The air inlet 47 and the air outlet 48 are provided to communicate with a central area defined between the outer body 31 and the sleeve 30, thereby forming a drainage structure. A pipe connected to the air inlet 47 is connected to and between the control valve 42 and the first pressure gauge 43 . A speed controller 49 and a third on/off valve 50 are mounted at a middle portion of the pipe in a state where the speed controller 49 and the third on/off valve 50 are arranged in parallel with each other. The speed controller 49 is provided to restrict an amount of air supplied to the middle area. The speed controller 49 is constructed to constantly supply a comparatively small amount of air to the central area. The third on/off valve 50 is normally kept in a closed state and is opened only when waterdrops are generated in the central area. By opening the third on/off valve 50, a large amount of cleaning air bypassing the speed controller 49 is blown to the central area so that waterdrops are removed. As described above, it is possible to prevent a phenomenon that steam generated from a high-temperature fluid material and steam used in the SIP permeate the stator 32 and reach the middle area, and then the middle area remain. If the vapor becomes waterdrops by cooling and water is stagnant as it is, bacteria or the like may be multiplied by the water to cause an unsanitary condition. By causing air to flow into the central area, it is possible to prevent such an unsanitary state from occurring with certainty. Due to a constant air supply in the middle area by the speed controller 49, it is hard to imagine that water droplets remain in the middle area. Accordingly, a flow passage on a third on/off valve 50 side is not essential.

The sleeve 30 is a cylindrical body made of an elastic material. An end opening portion of the sleeve 30 is between “an inner peripheral surface of the third housing 29 on one end side” and “the end port 34 and the first adapter 55, which will be described later”. A flange portion is formed at each end portion of the third housing 29 and the end port 34, and these flanges are held by a bracket 51. As shown in FIG. The other end opening portion of the sleeve 30 is located between “the inner peripheral surface of the third housing 29 on the other end side and the protective cover 37” and “an outer peripheral surface of the locking piece 36 and an outer peripheral surface of the ring-shaped protruding portion 38 of the locking piece 36”. With such a structure, the annular hermetic space 52 is formed between the sleeve 30 and the third housing 29 . A control fluid is filled into the hermetically sealed space 52 via the inlet port 39 and is discharged from the hermetically sealed space 52 via the outlet port 40 .

As in 6 As shown, the outer body 31 is formed of a plurality of (ten in this embodiment) outer portions 53 made of a synthetic resin material. Each of the outer portions 53 is formed of a bar-shaped body having an isosceles trapezoidal shape in cross section, and a projection 54 having a square shape in cross section protrudes from both end portions of each outer portion 53 . The projections 54 act as engaging portions to engage with recessed portions 58 (engaging portions) formed on the adapters 55, 56 described later. By bringing flat surfaces of leg portions (leg portion inclined surfaces 53a) of the outer portions 53 into contact with each other den, with upper bottom portions of the isosceles trapezoidal shapes being located on one side of an inner diameter, the outer portions 53 are brought into a ring-like lined-up state. In a state where the outer portions 53 are annularly lined up, both side surfaces 54a of each projection 54 are arranged in parallel with a straight line passing from the center O of the annularly connected projections 54 through the center of each outer portion 53 and advancing to direction of the outer diameter (only a straight line denoted by the symbol "CL" is drawn in 6B shown).

At both end portions of the outer body 31, the first adapter 55 and the second adapter 56 each being an example of a guide member are disposed respectively. Although each adapter 55, 56 as in 7 shown has a donut shape, each adapter 55, 56 having the donut shape is formed by combining two adapter parts 57 in this embodiment. An inner surface of each adapter 55, 56 has a polygonal shape (in this embodiment, a regular decagonal or decagonal shape) matching a shape of an outer peripheral surface of the stator 32 described later. Ten recessed portions 58 are on a surface of each adapter 55, 56 equidistant in the Circumferentially, and a screw hole 60 having a stepped shape is formed in each pedestal portion 59 defined between two recessed portions 58 . The projections 54 of the respective outer portions 53 are located in the respective recessed portions 58 . Each recessed portion 58 has opposite surfaces 58a guiding both side surfaces 54a of the projection 54 of the outer portion 53 and an inner side surface 58b located on the inner diameter side, and each recessed portion 58 is opened to the outer diameter side . By forming the recessed portions 58 into such a configuration, the protrusions 54 of the respective outer portions 53 are positioned in the circumferential direction while the protrusions 54 are movable in the radial direction. As described above, the recessed portions 58 form the portions to be engaged, which engage the protrusions 54 of the outer portions 53 . On the other surface side of each adapter 55, 56, a conically shaped wedge-shaped surface 55a, 56a is formed, respectively, where a diameter of an outer peripheral surface gradually decreases.

The first adapter 55 is attached to the end bolt 34 with screws using the screw holes 60 (see Fig 4 ). By such fastening with screws, the wedge-shaped surface 55a of the first adapter 55 is pushed by the annular protruding portion 35 of the end bolt 34 so that the wedge-shaped surface 55a is moved to the inner diameter side. That is, the tapered surface 55a and the annular protruding portion 35 form the sliding structure. With such a structure, an inner peripheral surface of the first adapter 55 is press-contacted with an outer peripheral surface of the stator 32 so that a favorable sealed state can be obtained. The second adapter 56 is fastened to the closure part 36 with screws by using the screw holes 60 (see Fig 5 ) be used. By such fastening with screws, the wedge-shaped surface 56a of the second adapter 56 is pushed by the annular protruding portion 38 of the locking member 36 so that the tapered surface 56a is moved toward the inner diameter side. With such a structure, an inner peripheral surface of the second adapter 56 is press-contacted with an outer peripheral surface of the stator 32 so that a favorable sealed state can be obtained.

The first adapter 55 and the second adapter 56 are provided at both end portions of each outer portion 53, and thus the movement of each outer portion 53 in the circumferential direction is restricted. In each outer portion 53, the projection 54 in the recessed portion 58 formed in the adapter 55, 56 is movable in the radial direction of the stator 32. As shown in FIG. That is, the outer portions 53 are moveable between a first position in which the outer portions 53 are capable of compressing the stator 32 and a second position in which the outer portions 53 relieve a state of compression of the stator 32 . Each outer portion 53 is formed from a rigid body. By causing a control fluid to flow into the hermetic space 52, the outer portions 53 are moved inward such that the outer portions 53 uniformly compress the entire stator 32 inward. Accordingly, there is no defect such as generation of a pulsation caused by varying a contact pressure between the stator 32 and the rotor 33 in the axial direction. When the outer portions 53 are moved radially inward, further movement of the outer portions 53 is prevented at a position where the leg portion inclined surfaces 53a are brought into contact with each other. Accordingly, there is no possibility that a contact pressure of the stator 32 on the rotor 33 is excessively increased. More precisely, the outer sections 53 are as in 8th shown movable in the radial direction of the stator 32 (the direction connecting a depth-facing or rear side and a viewing side or front side, and which is perpendicular to a paper plane on which a figure with respect to the outer Section 53 is drawn, which is on a in 8th center line shown). On the other hand, both side surfaces of the respective protrusion 54 of the outer portion 53 are guided by the both opposite surfaces 58a of the recessed portion 58 formed on the respective adapters 55, 56 (only the first adapter 55 is shown in Fig 8th shown), and thus each outer portion 53 in the circumferential direction of the stator 32 (in the perpendicular direction in 8th ) immobile. The outer portions 53 may be structured such that, in the second position, a compressive force of the outer portions 53 acting on the stator 32 becomes zero, so that the stator 32 is not compressed at all. However, the outer portions 53 are not limited to such a structure. It suffices that the outer portions 53 are structured such that at least a compression state of the stator 32 is weaker compared to a compression state of the stator 32 at the first position. The increase in a contact pressure of the stator 32 to the rotor 33 can be suppressed not only by contact between the leg portion inclined surfaces 53a of the outer portions 53 but also by contact between the projections 54 of the outer portions 53 and the inner side surfaces 58b of the recessed portions 58 formed on the adapters 55,56.

The stator 32 is formed of a cylindrical body made of an elastic material such as rubber or a synthetic resin desirably selected to match a material to be transported (for example, silicone rubber or fluorine rubber (which is used when a fluid material, that contains silicone oil, is cosmetic or the like)). In this embodiment, the stator 32 has a hollow cylindrical shape having a regular decagonal shape in cross section. An inner peripheral surface of a center hole 32a of the stator 32 is formed of single-start or multi-start (n-start) internal threads.

The rotor 33 has a shaft body made of a metal material such as stainless steel and having an outer peripheral surface formed of single-start or multi-start ((n-1) starts) male threads. The rotor 33 is disposed inside the center hole 32a of the stator 32 and forms a continuous conveying space 32b extending in the longitudinal direction of the rotor 33. As shown in FIG. An end portion of the rotor 33 is connected to the coupling rod 4 on the case side. Upon receiving a driving force from a driving unit (not shown in the figure), the rotor 33 rotates inside the stator 32 and revolves on an inner peripheral surface of the stator 32 at the same time. That is, the rotor 33 eccentrically rotates in the center hole 32a of the stator 32 so that the fluid material in the feed space 32b can be fed in the longitudinal direction of the rotor 33 .

Next, a method of assembling the uniaxial progressive cavity pump having the above structure will be described.

First, the locking member 36 is integrally assembled by, for example, being press-fitted to an end portion of the stator 32 into which the rotor 33 is inserted. Then the second adapter 56 is fastened to the closing part 36 with screws. The second adapter 56 is formed from two adapter sections 57 . By fixing the second adapter 56 to the locking member 36 with screws, the wedge-shaped surface 56a is pushed through the annular protruding portion 38 of the locking member 36 and is moved toward the inside. Accordingly, the inner surface of the second adapter 56 is brought into close contact with the outer surface of the stator 32 so that a favorable sealed state can be obtained. In the same manner, in a state where the end fitting 34 is integrally assembled to the other end portion of the stator 32, the first adapter 55 is assembled to the end fitting 34 with screws. In the same way as the second adapter 56, the first adapter 55 is also formed from two adapter sections 57. By fastening the first adapter 55 to the end fittings 34 with screws, the tapered surface 55a is pushed through the annular protruding portion 35 of the end fitting 34 and moved inward. Accordingly, the inner surface of the first adapter 55 is brought into close contact with the outer surface of the stator 32 so that a favorable sealed state can be obtained.

Thereafter, the outer sections 53 are each arranged along corresponding outer surfaces of the stator 32 . In this process, the projections 54 of the outer portions 53 are positioned in the recessed portions 58 formed in the first adapter 55 and the second adapter 56 . With such an operation, although the respective outer portions 53 are movable in the radial direction relative to the stator 32, the positions of the respective outer portions 53 in the circumferential direction are restricted. The sleeve 30 is placed around the outer body 31 formed by arranging ten outer portions 53 . Then, these parts are accommodated in the third case 29. One end portion of the third housing 29 is closed by the end port 34 and the other end portion of the third housing 29 is closed by the closing member 36 and the protective cover 37. Through these steps, the pump body 2 is completed.

An end portion of the coupling rod 4 is connected to the rotor 33 . An opening end portion of the first housing 1 is brought into contact with the protective cover 37, and the first housing 1 and the protective cover 37 are connected to each other by a clip not shown in the figure, thereby covering the coupling rod 4.

As in 9 shown, the mechanical seal 12 is mounted on the other end portion of the coupling rod 4. First, a fixed ring 14A is mounted on the coupling rod 4. Then, a rotating ring 14B is mounted on the coupling rod 4 and is brought into contact with an end face (an annular protruding portion 13a) of the fixed ring 14A. Then, the leg portions 24 of the adjusting plate 23 are slidably moved into the groove portions 22 (flat surfaces 21) from an outer diameter side of the coupling rod 4 . After the contact between a lower edge of the connecting portion 25 of the adjusting plate 23 as in FIG 13 1 and the locating pin 20 of the annular portion 16 of the rotating ring 14B has been made, the enlarged portions 26 are pushed by the index fingers while a thumb hooks the operating projections 28 of the adjustment plate 23 and pulls the operating projections 28. With such methods, the adjusting plate 23 is adjusted as in FIG 10 shown inclined in a state in which the adjusting plate 23 is supported by the groove portions 22 so that the positioning pin 20 is spaced from the lower edge of the connecting portion 25, whereby the adjusting plate 23 is further movable in a sliding manner. In this state of operation, the adjusting plate 23 plays a role as a tool that facilitates the pushing of the rotary ring 14B. Then the adjusting plate 23 as in 11 1 is slidably moved until the lower edge of the connecting portion 25 is brought into contact with the outer peripheral surface of the coupling rod 4, and thereafter the adjusting plate 23 is adjusted as shown in FIG 12 shown is brought from an inclined position to a home position, and the positioning pin 20 is inserted into the pin hole 27 formed in the adjusting plate 23. By releasing the hands in this step, the adjustment plate 23 is pushed by the annular portion 16 of the rotating ring 14B, which is biased by the spring 19 so that the contact between the adjustment plate 23 and a side surface 22a of the groove portion 22 is made, thereby adjusting the adjustment plate 23 is positioned (see 9 ). As described above, the rotating ring 14B can be easily mounted (temporarily fixed) on the coupling rod 4 without using any tool. By reversing the above procedure, the rotating ring 14B mounted on the coupling rod 4 can be easily removed.

After the mechanical seal 12 is mounted on the coupling rod 4 , the coupling rod 4 is connected to the drive transmission section 6 . That is, a distal end portion of the coupling rod 4 as in FIG 2 shown is inserted into the cylindrical portion 10 of the drive shaft 9, and an opening end surface of the seal cover 14a is brought into contact with an opening end surface of the second housing 7. Then the coupling rod 4 and the drive shaft 9 are connected to each other by means of the connecting pin 11 . In this state of operation, the distal end opening portion 9a of the cylindrical portion 10 pushes the adjusting plate 23, and thus the adjusting plate 23 is separated from the side surfaces 22a of the groove portions 22. A length of the cylindrical portion 10 in the axial direction is set to a value that allows the adjustment plate 23 and the rotating ring 14B to be moved to appropriate positions so that the spring 19 is brought into an appropriate compression state.

Next, the operation of the uniaxial progressive cavity pump having the above structure will be described.

A filling amount of a control fluid filled in the hermetically sealed space 52, a kind of the fluid material, and a relationship between a rotation speed of the rotor 33 and a discharge pressure are set in advance. For example, the sleeve 30 is placed in an initial state in which a capacity of a control fluid to be filled in the hermetically sealed space 52 is set to a minimum value. A relationship between a rotational speed of the rotor 33 and a discharge pressure is stored in the form of a data table for respective types of fluid material. By executing several similar processings when changing a filling amount of a control fluid filled in the hermetically sealed space 52 stepwise, a data table or map is completed.

When a fluid material is discharged from a tank or the like. First, the first on/off valve 41 is opened or a similar operation is performed so that a control fluid is filled in the hermetically sealed space 52 defined by the third housing 29 and the Sleeve 30 is formed. The outer body 31 made up of the numerous outer portions 53 is arranged at the end portion of the stator 32 . Both end portions of the respective outer portions 53 are supported by the adapters 55,56. With such a structure, the stator 32 is movable in the radial direction. Accordingly, interference between the stator 32 and the rotor 33 can be adjusted by changing a filling amount of control fluid filled in the hermetically sealed space 52, thereby moving the stator in the radial direction. A charge amount of the control fluid filled in the hermetically sealed space 52 is determined by referring to the data table to discharge a fluid material having a desired discharge pressure in accordance with the rotational speed of the rotor 33 . In this case, an incompressible fluid is preferably used as a control fluid because using an incompressible fluid makes it possible to make a relationship between a charge amount and a discharge pressure stable without fluctuation.

A discharge pressure can be increased as follows. By increasing a capacity of the control fluid to be filled in the hermetically sealed space 52, the sleeve 30 is elastically deformed toward the inside, so that the outer portions 53 are caused to come closer to each other. By causing the outer portions 53 to approach each other, the stator 32 is pressurized so that a contact pressure of the stator 32 on the rotor 33 is increased. On the other hand, a discharge pressure can be pressed as follows. By suppressing a filling amount of a control fluid, an amount of deformation of the sleeve 30 is suppressed so that the outer portions 53 are not caused to come much closer to each other. By causing the outer portions 53 not to come much closer to each other, contact pressure of the stator 32 with the rotor 33 can be suppressed.

After a filling quantity of a control fluid has been adjusted, the drive unit, not shown in the figure, is driven by means of the coupling rod 4 in such a way that the rotor 33 rotates at a predetermined speed. A rotation speed in this operating state is determined by considering a discharge amount per unit time. By rotating the rotor 33, a conveying space formed by the inner peripheral surface of the stator 32 and the outer peripheral surface of the rotor 33 moves in the longitudinal direction of the stator 32 and the rotor 33. A fluid material fed through the connecting pipe 5 is passed through the first housing 1 is sucked into the delivery chamber and is delivered to the end piece 34 . The fluid material that reaches the end port 34 is conveyed on to another place.

During an operation of the uniaxial progressive cavity pump, a state is created in which air continuously flows in a direction from the air flow inlet 47 to the air flow outlet 48 in the middle region defined between the outer body 31 and the sleeve 30 . With such a configuration, even when high-temperature fluid material that generates steam or steam itself is discharged, there is no possibility that steam permeating through the stator 32 remains in the third housing 29, so it is possible to discharge such vapor safely. Even if a state occurs in which waterdrops remain in the central area by some accident, it is enough to supply a large amount of air inside the central area by opening the third on/off valve 50 .

As already described, the entire outer peripheral surface of the stator 32 is held by the outer body 31 . In addition, the rotation of the outer body 31 in the circumferential direction is prevented by the adapters 55, 56 arranged at both end portions of the outer body 31. As shown in FIG. That is, the entire outer peripheral surface of the stator 32 is held by the entire inner surface of the outer body 31, the rotation of which is prevented by the adapters 55, 56 so that a torque load generated by the rotation of the rotor can be dispersed. Accordingly, it is possible to prevent the occurrence of repeated deformation in which the stator 32 is elastically deformed in the rotational direction along with the rotation of the rotor 33 and the stator 32 returns to an original shape thereafter. Accordingly, it is possible to prevent breakage of the stator 32 from occurring.

As in 14 As shown, the stator 32 is formed in a decagonal shape in cross section, and the outer body 31 is formed of ten outer portions 53 corresponding to the number of sides of the stator 32 in cross section. Accordingly, the stator 32 and the respective outer portions 53 can be brought into contact with each other, or can be separated from each other in a state where the outer surfaces of the stator 32 and the inner surfaces of the respective outer portions 53 face each other. Also, by increasing the number of the outer portions 53 compared to the case where the number of the outer portions 53 is small, it is possible to reduce a gap δ between the leg portion inclined surfaces 53a of the outer portions 53 adjacent to each other are located when the outer portions 53 are moved in the outer diameter direction. With such a structure, when the outer portions 53 move toward the stator 32 in a direction from the outer diameter side toward the inner diameter side, it is possible to prevent occurrence of a defect that the gap δ scratches the stator 32 so that the Stator 32 is damaged.

In addition, the sleeve 30 is arranged on the outer diameter side of the stator 32, and thus, even if a crack or the like forms on the stator 32, there is no possibility that outside air or the like enters the stator 32 or a fluid material in the stator 32 enters the environment leaks, so that the surrounding area is contaminated.

Also, when a high-temperature fluid material is conveyed as in the case where the inside of the stator 32 is to be sterilized, it is preferable to push a charge of a control fluid charged in the hermetically sealed space 52 (or a charge of a control fluid charged in the hermetically sealed space 52 filled with control fluid to zero). The stator 32 is thermally enlarged in the radial direction by the high-temperature fluid material. In this case, the respective outer portions 53 become movable toward the outer diameter side by reducing a charge amount of a control fluid. Accordingly, the stator 32 can be enlarged toward the outer diameter side, so that it is possible to prevent occurrence of a defect that the stator 32 expands only toward the inner diameter side, thereby stopping the rotation of the rotor 33 .

It is also preferable to adjust a charge amount of the control fluid by considering an amount of wear of the stator 32 or the rotor 33 generated during use of the stator 32 and the rotor 33 . That is, when the stator 32 and the rotor 33 are worn, a filling amount of the control fluid is increased by also taking such a wear amount into consideration, thereby adjusting an interference between the stator 32 and the rotor 33 to a desired value.

The present invention is not limited to the structures described in the embodiment, and various modifications are conceivable.

In the embodiment, the outer case 31 is formed of ten outer sections 53 . However, the number of outer sections 53 is not particularly limited, and the outer body 31 may be formed of six, eight, twelve or more outer sections 53 . The number of outer sections 53 can also be an odd number. However, for a balanced outer body 31, it is desirable to set the number of outer sections 53 to an even number. By increasing the number of outer sections 53, a gap size δ (see 14B) formed between the outer portions 53 located adjacent to each other when the outer portions 53 are moved toward the outer diameter direction. Accordingly, a defect such as a scratch is impossible to occur when the stator 32 is elongated or contracted in the radial direction.

In the embodiment, the projections 54 are formed on the outer body 31 as the engaging portions, and the recessed portions 58 are formed on the adapters 55, 56 as the portions to be engaged. However, the recessed portions may be formed on the outer body 31 as the engaging portions, and the projections may be formed on the adapters 55, 56 as the portions to be engaged.

In the embodiment, the entire outer body 31 is formed of only one synthetic resin material. As in 15 shown, however, a reinforcing plate 61 made of metal may be integrally mounted on the outer body 31 as a reinforcing body. That is, a plurality of recessed portions 58 are formed at predetermined portions along the longitudinal direction on a rear surface of each outer portion 53 constituting the outer body 31, and an inner nut 62 is integrally formed with each recessed portion 58. Stepped holes are formed in the reinforcing plate 61 and bolts 63 are threadedly engaged in the respective female nuts 62 through the stepped holes so that the reinforcing plate 61 is integrally mounted on the outer portion 53 .

When the outer portions 53 each reinforced by the metal-made reinforcing plate 61 are used, inner surfaces of the outer portions 53 made of a synthetic resin are brought into contact with the stator 32 disposed in the outer portions 53 and thus the stator 32 is minimally damaged, and a preferable surface contact state between the stator 32 and the outer portions 53 can be obtained. In addition, the strength of each outer portion 53 per se is increased by the reinforcing plate 61, and thus the outer portions 53 are minimally deformed (bent) due to heat, expansion of the stator 32, or the like. Accordingly, a state in which the stator 32 is sufficiently held by the outer body 31 can be secured.

The reinforcement plate 61 may be formed on each outer portion 53 by insert molding. In this case, a rod-shaped body made of a hard material is made can be used in place of the reinforcing plate 61. If it is ensured that the deformation of the outer body 31 can be prevented, a length of the bar-shaped body can be set shorter than a length of the outer body 31.

Alternatively, instead of mounting the reinforcing plate 61 to the outer body 31, protruding ridges or grooves extending in the longitudinal direction may be formed on the outer body 31 to cause the outer body 31 to have a cross-sectional shape that increases the strength of the outer body 31.

In the embodiment, when assembling the mechanical seal 12 on the coupling rod 4, the rotating ring 14B is temporarily fixed by the adjustment plate 23, and thereafter the rotating ring 14B is moved to an appropriate position when connecting the coupling rod 4 to the pump body side. However, the rotary ring 14B may be positioned at an appropriate position when the adjusting plate 23 is mounted on the coupling rod 4. In this case, it suffices to adjust the position of the groove portions 22 so that the adjusting plate 23 and the rotating ring 14B are located at appropriate positions and the spring 19 is suitably compressed when the adjusting plate 23 contacts the side surfaces 22a of the groove portions 22 is brought.

In the embodiment, only one adjustment plate 23 is used. However, a surface pressure of the mechanical seal 12 can be adjusted by using plural adjusting plates 23 or by preparing plural adjusting plates 23 having different thicknesses. Also, in addition to forming the pair of groove portions 22 having the flat surfaces 21 on the outer peripheral surface of the coupling rod 4, plural pairs of groove portions 22 may be formed on the outer peripheral surface of the coupling rod 4 while positions of the pairs of groove portions 22 in the axial direction and the Circumferential direction to be changed. By forming the groove portions 22 described above, a surface pressure of the mechanical seal 12 can be adjusted to match the difference in mounting position of the adjustment plate 23 .

In the embodiment, the groove portions 22 may have a width dimension substantially equal to a thickness of the adjusting plate 23, although the groove portions 22 formed on the coupling rod 4 have a width dimension allowing the adjusting plate 23 to move in the axial direction to move the coupling rod 4. However, it is preferable to set a width dimension of the groove portions 22 larger than a thickness of the adjusting plate 23 in order to facilitate mounting and detaching of the rotary ring 14B.

In the embodiment, the adjusting plate 23 is used for temporarily fixing (positioning) the rotary ring 14B. However, a pin or the like may be used to temporarily fix (position) the rotating ring 14B. For example, a pin 64 as in 16 shown can be made to pass through a through hole formed in the coupling rod 4, and the rotating ring 14B can be temporarily fixed (positioned) by the pin 64. In this case, a hole is formed in the pin 64 into which the positioning pin 20 formed on the annular portion 16 of the rotating ring 14B is insertable. The through hole formed in the coupling rod 4, through which the pin 64 can be inserted, can be an elongated hole 65, as in FIG 16B shown by a two-dot chain line. By forming the through hole as an elongated hole, the rotary ring 14B can be slid by inclining the pin 64 in the same manner as in the case of using the adjustment plate 23 .

In the embodiment, the outer portions 53 are moved in the radial direction by supplying/discharging a control fluid to/from the hermetic space 52 . However, the outer portions 53 can be moved in the radial direction by means of other driving means such as a magnet or a spring.

In the embodiment, the projections 54 of the respective outer portions 53 are supported by the adapters 55, 56 each formed of two divided members. However, the adapter 55, 56 may be formed of one piece or three or more divided pieces. With regard to ease of assembly, however, it is preferable for the adapter 55, 56 to be formed from divided elements.

In the embodiment, the supply of a control fluid to the inside of the hermetic space 52 in the third housing 29 and the supply of air to the intermediate region defined between the outer body 31 and the sleeve 30 are performed from the same supply source. However, the supply of control fluid and the air supply can be performed from different supply sources.

In the embodiment, the spring 19 may be disposed on the fixed ring 14A side, although the description has been made on the case where the spring 19 is disposed on the rotating ring 14B side. That is, the structure according to the embodiment can achieved not only by a so-called “rotating” mechanical seal, but also by a “static” mechanical seal.

Reference List

1

First housing

2

pump body

3

Stand or machine bed

4

coupling rod (rotating shaft)

5

connecting pipe

6

Drive transmission section or drive train

7

Second case

8th

camp

9

drive shaft

10

Cylindrical section

11

connecting pin

12

mechanical seal

13

seat ring

13a

Ring-shaped protruding section

14A

Fixed ring

14B

rotating ring

14a

sealing cover

14b

O ring

15

Powered ring

16

Annular section

17

O ring

18

guide pin

19

spring (elastic part)

20

positioning pin

21

flat surface

22

groove section (mounting section)

23

adjustment plate (mounting part)

24

leg section

25

connection section

26

Extended section

27

pin hole

28

operating projection section

29

Third case

30

sleeve

31

outer body

32

stator

33

rotor

34

end bolts

35

Ring-shaped protruding section

36

locking part

37

protective cover

38

Ring-shaped protruding section

39

inlet port

40

outlet port

41

First on/off valve

42

control valve

43

First pressure gauge

44

regulator

45

Second pressure gauge

46

Second on/off valve

47

air intake

48

air outlet

49

speed control

50

Third on/off valve

51

bracket

52

Hermetically sealed room

53

Outer Section

54

head Start

55

First adapter (guide part)

56

Second adapter (guide part)

57

Adapter Section (Guide Section)

58

Reset section

59

pedestal section

60

screw hole

61

reinforcement plate (reinforcement body)

62

inner mother

63

screw

64

Pen

65

Long hole

Claims (6)

A uniaxial progressive cavity pump comprising a housing (29), the housing (29) containing: a stator (32) having an internally threaded peripheral surface; a rotor (33) configured to be insertable into the stator (32) and composed of a shaft externally threaded body is formed; an outer body (31) disposed on an outside of the stator (32) and configured to move between a first position in which the outer body (31) is configured to compress the stator (32) and a second position is movable in which the outer body (31) reduces at least a compression state of the stator (32), the outer body (31) having a pair of end portions each including a pair of side faces; a pair of adapters (55, 56) provided at respective end portions of the outer body (31) and each including a recessed portion (58), each of the recessed portions having opposing surfaces for guiding both side surfaces of an associated one of the respective end portions of the outer body (31), and each of the recessed portions (58) is opened to an outer diameter side of the associated adapter (55, 56); and a sleeve (30) which is arranged on an outer diameter side of the outer body (31) and forms a hermetically sealed space (52) between the sleeve (30) and the housing (29), the sleeve (30) being structured to being elastically deformable in an inner diameter side of the sleeve (30) by filling a control fluid into the hermetically sealed space (52). Uniaxial progressing cavity pump claim 1 Further comprising a mounting section (22) on which at least one adapter (55, 56) can be mounted, wherein at least one adapter (55, 56) is ring-shaped and is mounted on the mounting section (22). Uniaxial progressing cavity pump claim 2 wherein at least one adapter (55, 56) is formed of plural adapter portions (57) formed by dividing at least one of the adapters (55, 56) in the circumferential direction, and the plural adapter portions (57) at the mounting portion in an annular continuous condition are mounted. Uniaxial progressing cavity pump claim 3 wherein at least one adapter (55, 56) and the mounting portion form a sliding structure configured to move the respective adapter portions (57) to an inner diameter side so that inner surfaces of the adapter portions (57) are in contact with an outer surface of the stator ( 32) can be brought into close contact when the mounting portion and the at least one adapter (55, 56) are connected to each other. Uniaxial progressing cavity pump according to one of Claims 1 until 4 , wherein a reinforcement body is provided integrally on the outer body. Uniaxial progressing cavity pump according to one of Claims 1 until 5 , wherein the housing (29) encloses the stator (32) and the outer body (31), and the housing (29) further comprises an outlet (48) for removing steam or water from a space in which the stator (32) and the outer body (31) are arranged.

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